Nozzle design for a fabric web treating facility

ABSTRACT

A nozzle design for particular use with a fabric web treatment facility in which heated air is periodically impinged against the web through nozzles as it is processed through the facility around a plurality of elongated rolls. The design provides for ease of access into the facility for cleaning and threading the web onto the rolls by providing a pivotal mounting for the nozzles in order that they may be arcuately moved between a first operative position closely spaced to the web and a second position spaced remote therefrom. Each nozzle includes three air outlet passages extending transversely thereacross in order that the heated air flow therethrough will impinge the web at varied angles and eliminate return air velocities.

[ 11 3,736,669 51 June5,1973

United States Patent 1 Amidon, Jr. et al.

[54] NOZZLE DESIGN FOR A FABRIC WEB 3,099,541 7/l963Hildebrand...i............ 3,257,938 6/1966Goyette.......',........................

TREATING FACILITY e u s my sum W.B n w nm 83 Kqm .T n me imy m e a mxM EE y W n at m m 18! f8! PAA r r mm r m I a G M. va m P Aflf 0 mh "aim bSF: e flaw a .m Cmr m r m n e v n I F 7 [73] Assignee: Gulf & WesternSystems Company,

New York, NY.

[57] ABSTRACT A nozzle design for particular use with a fabric webtreatment facility in which heated air is periodically impinged againstthe web through nozzles as ,it is processed through the facility arounda plurality of elongated rolls. The design provides for ease. of accessinto the facility for cleaning and threading the web onto the rolls byproviding a pivotal mounting for the nozzles in order that they may bearcuately moved between a first operative position closely spaced to theweb and a second position spaced remote therefrom.

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Each nozzle includes three airoutlet passages extend- UNITED STATESPATENTS ing transversely thereacross in order that the heated Hargett um 5 m m m 0 ac ZD 9895 6366 9999 1111 ///l 4 5 8496 3020 5733 3328 4 43233 d .m r. a v t a b w ea m hfi u n m 60 F gn w m p m m H mm D wm 6..nm Gm e m UT. :I 0a a In i C mm 8 ad m wa 08 it .un aa 4954 12 1 1 1//9/ 4454 393 3 2 Gustafsson et a].

PATENTEUJUH 5 I975 SHEET 1 HF FIG. I

ATTORNEYS PAIENTEUJUH 5 I975 SHEETEUFS INVENTOR.

CHARLES H. AMIDON, JR. BY VINCENT A. GALEONE Mequfldfimm; 23 Body FIG. 5

ATTORNEYS PAIENTEDJUH 19B 3. 736,669

sum 3 0F 3 INVENTOR. CHARLES H. AMIDON, JR.

By VINCENT A. G ALEONE M w/um, a M,

ATTORNEYS I NOZZLE DESIGN FOR A FABRIC WEB TREATING FACILITY Thisapplication pertains to the art of fabric treatment and moreparticularly to a nozzle design for use with a fabric web treatmentfacility.

The invention is particularly applicable to a fabric web treatmentfacility wherein a heated air flow is directed by a plurality of nozzlesto impinge a fabric web as it is processed through the facility around aplurality of elongated rolls and will be described with particularreference thereto; however, it will be appreciated that the inventionhas broader applications and may be used in any environments where it isdesired to direct a gaseous flow to impinge a fabric web or otherworkpieces.

In fabric web treatment, it is often desired to pass the In accordancewith a more limited aspect of the present invention, the plurality ofoutlet passages comprises three passages. The middle or central passageis disposed so as to direct a portion of the gas flow in a directionnormal to the web when the nozzle is in the first position. The othertwo passages are disposed so as to direct portions of the gas flowagainst the web at angles to the normal direction.

webthrough a facility wherein a heated air flow is periodically directedagainst the web. Such treatment may be alternately desired to dry and/orcondition the web.

A facility of this type generally employs a plurality of elongated rollsspaced adjacent to and parallel with each other so as to form at leastone column or row of rolls which may be enclosed in a housing. The webis threaded between adjacent rolls in a serpentine fashion and a heatedair flow directed to impinge the web by nozzles spaced adjacent eachroll.

Heretofore, these fabric web treatment facilities utilized a pluralityof fixed nozzles placed in closely spaced relationships relative to theweb. Because of this arrangement, the nozzles were necessarily locatedapproximately 6 to 10 inches away from the web to enable maintenancework to be perfonned on the facility,

to provide a clearance area for cleaning the rolls, and to permitthreading of the web around the rolls. Because of this necessarydistance, the effective velocity of the heated air flow issuing from thenozzles was substantially reduced so that the receipt of an efficientheat transfer from the air to the web was greatly impaired. Further,these prior nozzles only utilized a single air outlet passage disposedadjacent the web so that the air was directed to impinge the web only ina direction generally normal thereto. This single outlet passage did-notprovide a particularly efficient impinging air supply against the fabricweb so that many rolls and associated single outlet passage nozzles wererequired to dry and/or work the web as desired. Further, in priorfacilities of this type, each nozzle formed a part of a plenum chamberwhich confined the air after it had impinged the web and causedtransverse velocities of air resulting in uneven heating of the webselvedges.

The present invention contemplates a new and improved apparatus whichovercomes all of the above referred problems and others and provides anozzle design for a fabric web treatment facility which provides ease ofaccess for cleaning the facility components and which provides moreefficient air impingement on the fabric web.

In accordance with the present invention, there is provided a gas flowsupply nozzle for particular use with a fabric web treatment facility.The nozzle is comprised of an elongated housing including a gas inletarea disposed adjacent one end thereof and a plurality of gas outletpassages disposed across the other end in a generally side by siderelationship. The nozzle is mounted relative to the facility in orderthat it may be selectively moved between a first position in closelyspaced operative relationship relative to the web and a second positionspaced remote therefrom.

In accordance with another limited aspect of the present invention, theangled outlet passages are each disposed to direct gas outwardly at anangle of approximately 30 from the normal.

The principal object of the present invention is the provision of a newand improved gas flow nozzle for use in a fabric web treatment facility.

Another object of the present invention is the provision of a new andimproved gas flow nozzle for use in a fabric web treatment facilitywherein the nozzle is movable between a first operative positionrelative to the web to a second position spaced remote therefrom.

Another object of the present invention is the provision of a new andimproved gas. flow nozzle for use in a fabric web treatment facilitywhich improves gas flow impingement onto the fabric web. v

Still another object of the present invention is the provision of a newand improved gas flow nozzle for use in a fabric web treatment facilitywhich permits the nozzle to be closely spaced to the fabric web when inthe operative position.

Yet another object of the present invention is the provision of a newand improved gas flow nozzle for use in a fabric web treatment facilitywhich eliminates return air velocities.

The invention may take physical form in certain parts and arrangementsof parts, a preferred embodiment of which will be described in detail inthis specification and illustrated in the accompanying drawings whichform a part hereof and wherein:

FIG. 1 is a side view of a fabric web treatment facility using theconcepts of the subject invention and having a portion of the side wallremoved for ease of illustration;

FIG. 2 is a view of three warm air nozzle assemblies constructed inaccordance with the subject invention and which have been arcuatelymoved from the operative position for cleaning or threading of thefacility;

FIG. 3 is a plan view of one of the warm air nozzle assemblies of thesubject invention;

FIG. 4 is a cross sectional view taken along lines 4-4 of FIG. 3;

FIG. 5 is an enlarged view of the air outlet passages in one of the warmair nozzle assemblies; and,

FIG. 6 is a cross sectional view taken along lines 6-6 of FIG. 4.

Referring now to the drawings, wherein the showings are for the purposesof illustrating the preferred em bodiment of the invention only and notfor purposes of limiting same, the FIGURES show a fabric web treatmentfacility A including therein warm air circulating units B, fabric webroll assemblies C and warm air nozzle assemblies D.

More specifically, the treatment facility includes a pair of spacedapart side walls 10,12 a front wall 14, a rear wall 16, a top wall 18,and a bottom wall 20. These walls may be constructed from any convenientmaterial such as sheet metal or the like and include extendingtherebetween and therealong any necessary and appropriate rigid framemembers. The facility is not shown in more detail as it, in and ofitself, does not form a part of the present invention and as it maycomprise any design necessary to fulfill a particular fabric treatmentfunction. Front wall 14 includes a fabric web inlet slot 22 and rearwall 16 includes a fabric web outlet slot 24. Further, side walls 10,12may include a plurality of access doors (not shown) which readily permitaccess to the inside of the treatment facility itself.

Disposed on top wall 18 are a pair of warm air circulating units Bcomprised of conventional circulating ducts and components generallydesignated 30,32 which, in the preferred embodiment, are driven byelectric motors 34,36 to generate air flow through the facility. Itshould be noted that unit 30 includes an air supply duct 38 extendinggenerally vertically along the inside of a portion of side wall and anair supply duct 40 in an identical relationship with side wall 12.Likewise, a second pair of air supply ducts 42,44 are disposed inassociation with heating and circulating unit 32 and side walls 10,12respectively. The air flow through these ducts will be more fullydescribed hereinbelow relative to operation of the apparatus. A heater46 is disposed in an operative relationship with circulating unit 30 anda heater 48 is disposed in operative relationship with circulating unit32 in order to heat the air being circulated inside of the facility. Inthe preferred embodiment, heaters 46,48 are mounted to and extendthrough side wall 10. Heaters 46,48 are only shown in a general mannerand may comprise any of several types of heaters adaptable for such use.An exhaust duct 50 is provided between units 30,32 to connect the insideof the facility with ambient air in order to assist in providing acontinuous flow of air within the facility.

An l-beam like channel member 60 extends vertically upward along eachside wall 10,12 at generally the midpoints thereof. Each channel memberincludes a base portion 62 and a plurality of pillow block mountings 64spaced longitudinally therealong on each side thereof. These pillowblock mountings are for mounting elongated rolls in position relative tothe facility and the number of pillow blocks employed depends entirelyupon the number of rolls to be used. In the preferred embodiment, tenelongated cylindrical rolls 66 are used and are journaled in a knownfashion between the associated of the pillow block mountings 64 of thetwo channel members so as to form two vertical columns or rolls. It is,of course, possible to have other spacial relationships between therolls and still use the concepts of the subject invention. It will beappreciated that the opposed channel members must be rigidly mounted tosupport these rolls, which rigid mounting may take the form of any ofseveral structural reinforcements which do not form a part of thepresent invention and are therefore not shown. It should be noted thatrolls 66 may be comprised of any material consistent with use for fabricweb treatment such as, for example, stainless steel or steel rollscovered by a synthetic material. Disposed atone end of each roll is asprocket-like element 68 for use in rotatably driving each of the rollsas will hereinafter be more fully described. Spaced adjacent fromchannel member 60 or mounted therefrom in any convenient manner areidler sprocket elements 70,72 and 74. In the preferred embodiment, theseelements are adapted to receive a drive chain 76 which extends in acontinuous fashion therearound and also around each sprocket-likeelement 68 associated with rolls 66. A drive motor generally designated78 and of the type generally associated with rotatably driving aplurality of rolls is mounted relative to bottom wall 20 in a knownfashion and a second continuous drive chain 80 extends between the drivemotor and sprocket-like element 70. The drive motor effects resultantrotational movement between each of rolls 66, the speed of which may bevaried by altering the sizes of the sprocket-like elements and/or thedrive motor speed in a known fashion. As far as the present invention isconcerned, it is merely necessary to appreciate that rolls 66 are drivenat identical speeds.

The overall arrangement for warm air nozzle assemblies D is best shownin FIG. 1. In that FIGURE, it will be noted that for each roll 66, anassociated nozzle as sembly is mounted in a cooperating relationshiptherewith adjacent thereto. Referring more specifically to FIGS. 3, 4, 5and 6, description of one of these assemblies will hereinafter be made,it being understood that the remainder of the assemblies are identicalthereto unless otherwise specifically noted. Assembly D is comprised ofa nozzle housing having anvair supply area generally designated 92 andan air outlet area generally designated 94. Housing 90 is comprised of atop wall 96, bottom wall 98 and a pair of spaced apart side walls100,102. It should be noted that in the preferred embodiment, thesewalls are made from a relatively thin walled rigid material such as, forexample, sheet metal, although other materials could be employed.Further, it should be noted that the top and bottom walls are formedfrom a single piece of sheet metal and that the housing is so designedthat the top and bottom walls converge toward each other from air supplyarea 92 to air outlet area 94. As shown, the housing is assembled byusing a plurality of mechanical fasteners designated 104, although othermeans such as welding or adhesives could be utilized. Disposed along thetop wall is an access area 106 which includes an access area cover 108thereover which is retained in position by mechanical fastening means orother convenient means. Disposed in each of side walls 100,102 is agenerally circular air supply inlet 1 10. Corresponding, generallycircular and outwardly extending, mounting flanges 120,122 are mountedaround air supply inlets 110 in walls 100,102 respectively.Corresponding receiving flanges 130,132 extend inwardly from ducts 42,44respectively to receive mounting flanges 120,122. Each of thesereceiving flanges is identical and, as best shown in FIG. 6, flange 132is designed to provide a circular gasket receiving channel 133 extendingtherearound. A gasket-like member 134 which may be comprised of rubberor similar material is received in channel 133 in order to provide arelatively air-tight sealing relationship between mounting flanges120,122 and receiving flanges 130,132. As may also be best seen in FIG.6, duct 44 includes an air outletpassage area 136 therein inside theconfines defined by receiving flange 132. It should be here noted thateach of air supply ducts 38, 40, 42 and 44 include similar air supplyoutlets as required to facilitate operative mounting for the desirednumber of nozzle assemblies D.

With mounting flanges 120,122 received inside of receiving flanges130,132 respectively and with the receiving flanges mounted to theirrespective air supply ducts, it will be appreciated that nozzle housing90 may be pivoted about that mounting so that air outlet area 94 may bemoved from, and with reference to FIG. 1, a closely disposedrelationship with the associated roll 66 to a second position, and withreference to FIG. 2, arcuately spaced therefrom so that a clearance areais developed between each of the rolls and its associated nozzleassembly. In the preferred embodiment of the subject invention and withthe nozzle assemblies in the first position, air outlet areas 94 aredisposed approximately two inches away from their associated rolls. Inthe second position, however, the nozzles are disposed approximately 18inches away from their associated rolls. This eighteen inch clearance ismore than sufficient to provide access to the rolls and/or nozzles forcleaning or maintenance purposes as will hereinafter be more fullyapparent. If tight-fitting relationships exist between receiving flanges130,132, gaskets 134, and mounting flanges 120,122, the nozzleassemblies will remain focused as positioned without the need forlocking means. However, simple locking means for positively locking eachof the nozzles in desired location may be easily provided. Further, itis also possible to interconnect all the nozzle assemblies so that theymay be simultaneously automatically moved between their first and secondpositions.

FIGS. 3, 4 and 5 best show outlet area 94 which is comprised of airoutlet passages 140,142 and 144. These passage areas may be fabricatedfrom any relatively thin rigid material such as sheet metal and affixedto the end of housing 90 by any convenient means such as, for example,mechanical fasteners. As seen in FIG. 4, these passages extendtransversely across housing 90 in a side by side relationship betweenside walls 100,102 and have reinforcements 146 extending laterallytherebetween to provide rigidity for the structure. As can beappreciated, it is most desirous that the transverse width of housing 90and the resultant width of each air outlet passage is at least as wideas the fabric web to be treated. Therefore, it is advantageous to havethis width substantially the same dimension as the length of rolls 66.As best seen in FIGS. 4 and 5, air outlet passage 1l40 is situated so asto direct a portion of the air flow from the nozzle housinglongitudinally coextensive with the housing itself. When the housing isin the first position, this causes an air flow to be directed againstthe surface of the associated roll 66 in a direction generally normalthereto. Passages 142,144 are disposed so as to direct the remainder ofthe air flow angularly outward from the nozzle housing at an angle tothe normal flow. In the preferred embodiment, and most advantageously,this angle is 30 as it has been found that this angle provides the mostefficient air impingement onto the surface of roll 66 and the fabricweb. Obviously, other angles could be used or even ad ditional passageareas could be used if desired.

In using the subject invention, all the warm air nozzle assemblies D arefirst moved to a position similar to that shown in FIG. 2. A fabric webgenerally designated W which may have previously been treated in aliquid cleaning or dying substance such that it is desired to dry it byimpinging warm air thereagainst as it travels through treatment facilityA is supplied for processing therethrough. The lead end is insertedthrough fabric web inlet 22 in front wall 14 and threaded in aserpentine fashion back and forth between the two vertical 6 columns orrolls 66 and then out through fabric web outlet 24 in rear wall 16. Theweb may be supplied from a reel (not shown) generally associated withfabric web handling and rerolled adjacent the outlet area by a takeupreel (not shown) also of a type used in fabric web handling. As shown inFIG. 1, appropriate leadin roll and exit roll 152 are also provided tosupport the web. Once the fabric web has been threaded into thefacility, nozzle assemblies D may be moved to their first positions asshown in FIG. 1.

The warm air circulating units B may next be energized to provide acontinuous flow of warm air through air supply ducts 38, 40, 42 and 44and out through outlets 136 into the associated of the nozzleassemblies. At the same time, heaters 46,48 are activated to heat thisair flow in order that warm air will be impinged against the fabric web.The air flow path is shown best in FIG. 1 by arrows designated s for thesupply air passed through ducts 38, 40, 42 and 44 and r for the returnair flow which will be reheated and recirculated. The web may then bepulled through the apparatus by the effect of drive motor 78 rotatinglydriving in unison all the rolls 66 and the takeup roll. As the webpasses between the rolls in the serpentine pattern, one column of theair nozzle assemblies will impinge warm air against one side of the weband the other column of air nozzle assemblies will impinge warm airagainst the other side of I the web. Thus, both sides of the web receivea flow of warm air thereagainst to dry or otherwise treat the web. Ascan best be seen in FIG. 5, air passing out of each nozzle assembly hasthe effect of directing a warm air flow to impinge the web at differentangles and is designated i therein. Once this air has impinged the web,it is in effect converted into a portion of return airflow r. Therefore,once the impinging air has expended its energy to the web, it bouncesback and returns away from the web so that it is free to return to therecirculating system for reheating and reimpinging.

Once the roll of fabric web has been processed, it is merely necessaryto again return the nozzle assemblies to the second positions in orderthat another roll of fabric web may be threaded and processed throughthe facility. As can be appreciated, it will oftentimes be desirous ofhaving access to the inside of the facility, and in particular, thesurface of the rolls in order to perform maintenance periodic cleaning.With the nozzle assemblies in the positions shown in FIG. 2, and withthe access doors in side walls 10,12 this is easily accomplished as, inthe preferred embodiment, a distance between the assemblies and rolls ofl8 inches is provided.

This distance is such that maintenance personnel will have free accessthereto to perform whatever maintenance for cleaning is deemednecessary. Similarly, access area covers 108 may be removed from theassociated access areas 106 in order to provide access into the insideof each nozzle assembly.

The invention has been described with reference to the preferredembodiment. Obviously, modifications and alterations will occur toothers upon the reading and understanding of this specification. It isour intention to include all such modifications and alterations insofaras they come within the scope of the appended claims or the equivalencethereto.

Having thus described our invention, we now claim:

1. A gas flow supply nozzle for particular use in treating a fabric webas it is continuously passed through a web treatment facility, saidnozzle comprising:

an elongated housing;

means for mounting said housing relative to said facility and means forselectively moving said housing between a first position in an operativerelationship with said web and a second position spaced remote from saidweb; and,

at least one gas inlet area disposed adjacent one end of said housingand means for forming a plurality of gas outlet passages disposedadjacent the other end of said housing, said plurality of gas outletpassages comprising at least three of said gas outlet passages extendingin a generally side by side relationship laterally across said other endwherein said first position one of said at least three passages isdisposed so as to direct a portion of said gas flow generallylongitudinally outward from said housing substantially transverselyacross said web and the other of said at least three passages aredisposed so as to direct portions of said gas flow outwardly from saidhousing at angles to the gas flow issuing from said one passage.

2. The nozzle as defined in claim 1 wherein said mounting meanscomprises means for pivotally mounting said housing adjacent said oneend for permitting said other end to be arcuately moved between saidfirst and second positions.

3. The nozzle as defined in claim 1 wherein said at least three outletpassages comprise three of said passages, said one passage comprisingthe middle one of said three passagesand said angles comprisingdiverging angles of approximately 30 from each side of the gas flowissuing from said one passage.

4. The nozzle as defined in claim 3 wherein said housing has a generallyrectangular cross section defined by a pair of opposed side walls, a topwall and a bottom wall, said top and bottom walls converging toward eachother from said one toward said other end, said three outlet passagesextending transversely across said other end between said side walls.

5. The nozzle as defined in claim 4 wherein said mounting means aredisposed in said side walls, said at least one gas inlet area beingdisposed inside at least one of said mounting means.

6. In a fabric treatment facility wherein a fabric web is passedcontinuously over a plurality of rolls while a gas flow is directedagainst said web from at least one nozzle assembly, the improvementcomprising:

said nozzle assembly including means for forming a plurality of adjacentoutlet passages, each of said plurality extending generally transverselyacross said assembly in a generally side by side relationship forseparating said gas flow into separate gas streams which each impingesaid web generally transversely thereacross at varied angles relative toeach other from said nozzle assembly, said nozzle assembly includingmeans for mounting said assembly for permitting selective movement ofsaid plurality of outlet passages between a first operative positionadjacent said web and a second position spaced remote therefrom, saidpassages extending generally transverse to said web when said outletpassages are in said first position.

7. The improvement as defined in claim 6 wherein said pluralitycomprises three of said outlet passages in a coextensive side by siderelationship, one of said outlet passages being disposed so as to directa portion of said gas flow against said web in a direction generallynormal thereto when said outlet passages are in said first position andthe other of said outlet passages being disposed so as to simultaneouslydirect portions of said gas flow against said web at angles to saidnormal direction.

8. The improvement as defined in claim 7 wherein said one outlet passagecomprises the center one of said three outlet passages and said otheroutlet passages are disposed so as to direct said portions against saidweb at a diverging angle of approximately 30 from each side of saidnormal direction.

1. A gas flow supply nozzle for particular use in treating a fabric webas it is continuously passed through a web treatment facility, saidnozzle comprising: an elongated housing; means for mounting said housingrelative to said facility and means for selectively moving said housingbetween a first position in an operative relationship with said web anda second position spaced remote from said web; and, at least one gasinlet area disposed adjacent one end of said housing and means forforming a plurality of gas outlet passages disposed adjacent the otherend of said housing, said plurality of gas outlet passages comprising atleast three of said gas outlet passages extending in a generally side byside relationship laterally across said other end wherein said firstposition one of said at least three passages is disposed so as to directa portion of said gas flow generally longitudinally outward from saidhousing substantially transversely across said web and the other of saidat least three passages are disposed so as to direct portions of saidgas flow outwardly from said housing at angles to the gas flow issuingfrom said one passage.
 2. The nozzle as defined in claim 1 wherein saidmounting means comprises means for pivotally mounting said housingadjacent said one end for permitting said other end to be arcuatelymoved between said first and second positions.
 3. The nozzle as definedin claim 1 wherein said at least three outlet passages comprise three ofsaid passages, said one passage comprising the middle one of said threepassages and said angles comprising diverging angles of approximately30* from each side of the gas flow issuing from said one passage.
 4. Thenozzle as defined in claim 3 wherein said housing has a generallyrectangular cross section defined by a pair of opposed side walls, a topwall and a bottom wall, said top and bottom walls converging toward eachother from said one toward said other end, said three outlet passagesextending transversely across said other end between said side walls. 5.The nozzle as defined in claim 4 wherein said mounting means aredisposed in said side walls, said at least one gas inlet area beingdisposed inside at least one of said mounting means.
 6. In a fabrictreatment facility wherein a fabric web is passed continuously over aplurality of rolls while a gas flow is directed against said web from atleast one nozzle assembly, the improvement comprising: said nozzleassembly including means for forming a plurality of adjacent outletpassages, each of said plurality extending generally transversely acrosssaid assembly in a generally side by side relationship for separatingsaid gas flow into separate gas streams which each impinge said webgenerally transversely thereacross at varied angles relative to eachother from said nozzle assembly, said nozzle assembly including meansfor mounting said assembly for permitting selective movement of saidplurality of outlet passages between a first operative position adjacentsaid web and a second position spaced remote therefrom, said passagesextending generally transverse to said web when said outlet passages arein said first position.
 7. The improvement as defined in claim 6 whereinsaid plurality comprises three of said outlet passages in a coextensiveside by side relationship, one of said outlet passages being disposed soas to direct a portion of said gas flow against said web in a directiongenerally normal thereto when said outlet passages are in said firstposition and the other of said outlet passages being disposed so as tosimultaneously direct portions of said gas flow against said web atangles to said normal direction.
 8. The improvement as defined in claim7 wherein said one outlet passage comprises the center one of said threeoutlet passages and said other outlet passages are disposed so as todirect said portions against said web at a diverging angle ofapproximately 30* from each side of said normal direction.